Shotgun shell with metal cap

ABSTRACT

A shotgun shell having a metal cap made from sheet metal. The metal cap includes an annular fold which provides a strong cap to body attachment and an integrally formed primer pocket and anvil. The basewad can be eliminated in order to make extra volume available within the shell for additional propellant and/or projectile load.

provides a e eliminated in order to make extra volume available withinthe shell for additional propellant and/or projectile load.

egrally formed [151 3,656,434 [451 Apr. 18, 1972 3,103,170 9/1963Covington,Jr.etal.................. 3,157,121 ll/1964 Daubenspeck etal,.... 3,215,077 11/1965 Mayer et Inc.

FOREIGN PATENTS OR APPLICATIONS 11,079 1915 GreatBritain..........................,

Primary Examiner-Robert F. Stahl Attorney-John H. Lewis, Jr. andNicholas Skovran [57] ABSTRACT A shotgun shell having a metal cap madefrom sheet metal. The metal cap includes an annular fold which strongcap to body attachment and an int primer pocket and anvil. The basewadcan b 12 Claims, 8 Drawing Figures MM U 00 11 Arms Company,

.102/43 P, 102/42, 102/44 ....F42b 5/30, F42b 7/06 102/38,42, 43,44, 43P Bailey........................... Guignet.................... 7/1963Daubenspeck et References Cited UNITED STATES PATENTS 3/1902 1,974,2709/1934 3,099,958

Roger J. Curran, Stratford, Conn.

Remington Bridgeport, Conn.

May 26, 1969 Int. 694,713

Uited States Patent Curran I54] SHOTGUN SHELL WITH METAL CAP [72]Inventor:

[73] Assignee:

[22] Filed:

[21] Appl. No.:

[58] Field ofSearch.........................

SHEET 10F 2 PATENTEDAP 18|972 gall? Inventor 1 'Attornqg SHOTGUN SHELLWITH METAL CAP This invention relates to ammunition and in general toplastic bodied shotgun shells. More specifically, the invention relatesto a shotgun shell having a plastic body and a metal cap in which theconventional basewad can be eliminated.

Shotshells are presently being designed and developed to take advantageof the cost and technical advantages which plastics offer. The presenttrend, therefore, is toward the use of less metal in shotshell designs.However, metals technology has also progressed beyond its present use inshotshell construction. Historically, the transition from paper toplastic body tubes was accomplished without much change in the functionthe metal portion served. Hence, differences between plastic and paperbody tubes were not used to full advantage in these designs inconsideration of the combination of metal with plastic. Likewise, primerdesign has not responded to changes in design and performance of theentire shotshell.

The concept of designing an entire shotshell rather than a series ofshotshell components leads to useful designs which offers, at theexpense of frugal compromises, certain degrees of freedom with respectto performance and cost.

To those shotshell users who do not reload (and it is believed thatthese are the great majority of shooters), there is some excess costassociated with any shotshell which may be reloaded. Linked with thiscost is the requirement that any shotshell must fail safely no matterthe number of reloadings. Because of the uncertainties of the reloadingcycle, it should be possible to design a shotshell, with adequate safetyfactor for one firing, at a lower cost than one designed for more thanone firing.

This invention deals with a shotshell design which combines safeperformance, low cost of construction, and increased ballisticperformance freedom and which may utilize a non-reloadable feature.Obviously, some of the elements of this design are not limited to theconcept of a non-reloadable shotshell.

Shotshells have undergone various modifications through the years.Shotshell casings changed from metal, to paper, and finally to plastic.When the all-metal shell was used, a basewad was not necessary since themetal head portion was strong enough to absorb the shock of firing andthe metal tubular body obturated sufficiently to provide an adequate gasseal. When the paper tubular body was introduced, it was found that somesort of reinforcing was necessary at the breech or head end of theshell. For example, U.S. Pat. No. 610,660, issued Sept. 13, 1898, showsan outer metal cap and an inner support cylinder to provide support forthe boiler-room or cavity where the propellant means is ignited.Subsequently, a separate basewad was inserted at the breech end toprovide necessary gas sealing and shock absorbing functions. The use ofa basewad was carried over to plastic-bodied shotshells, first whenoriented tubing was used for the cartridge bodies the later when anintegrally formed basewad was provided for the cold-formed one-piececartridge casings.

The use of a basewad, however, requires sacrificing of valuable volumein the shotshell. This lack of shotshell volume becomes important inview of the present day search for a substitute for lead shot. Becauseof the problem caused be lead poisoning of wild fowl, iron shot appearsto be the most promising candidate to replace lead, at least for fieldloads most often used by duck hunters. Having lesser density than lead,more volume of iron shot is needed to provide an equivalent load at thetarget.

The present invention is designed to provide a maximum volume load inpermitting the elimination of the basewad but at the same time insuringthat the sheet metal cap and plastic body construction are strong enoughto perform. It must be recognized, however, that the unique cap to bodyattachment can also be used with a basewad, if for any reason this isdeemed desirable.

It is an object of this invention to provide a plastic-bodied shotshellhaving a metal cap in which the cap and the cap to plastic bodyattachment are strong enough to eliminate the need for a basewad.

It is another object of this invention to to plastic body attachment.

It is another object of this invention to provide a novel sheet metalcap to which a primer pocket and anvil are integrally formed.

It is still another object of this invention to provide a shotshelldesign having a maximum volume thus increasing the capacity for shotloads.

Other objects and advantages will be apparent from the followingdescription and accompanying drawings in which:

FIG. 1 shows a front elevational view of a loaded shotshell cartridgeillustrating the invention;

FIG. 2 shows an expanded cross-sectional view of the breech end of thecartridge;

FIG. 3 shows an expanded cross-sectional view of the metal cap-bodyattachment;

FIG. 4 shows an expanded cross-sectional view of the primer pocket andanvil;

FIG. 5 shows a modification in which the metal cap has an integralprimer pocket only and a conventional center-fire type primer is used;

FIG. 6 shows a modification in which the fold has a differentconfiguration;

FIG. 7 shows another modified form of fold; and

FIG. 8 shows still another modified fold.

FIG. 1 shows a loaded shotshell 10 in which reference numeral l2 refersto a plastic body member and 14 refers to a metal cap member 14. Bodymember is preferably made of oriented plastic, e.g., polyethylene,polypropylene, etc., although obviously it may be made of any plasticmaterial, such as polycarbonate, which can be deformed to form the bodycap attachment and which has adequate physical characteristics towithstand firing conditions. FIG. 1 also shows a load of shot pellets16, filler wad means 18, and propellant means 20. It can be seen thatthere is no basewad as such.

This invention is concerned mainly with the breech end of the plasticbody member and its attachment with the metal cap and the details of themetal cap.

Plastic body member 12 is shown as a straight walled tube having aninner wall surface 22 and an outer wall surface 24. Obviously, eitherone or both of the wall surfaces can be tapered without affecting theinvention. The breech end of the body member, which is closed off by themetal cap member, is deformed to form an enlarged shoe 26 which has anoutwardly directed flange 28 which forms a rim and an inwardly directedgas-sealing flange 30, preferably, but not necessarily, of lesserthickness than the rim flange. The function of gas-sealing flange 30will be explained later.

The metal cap member 14 has a tubular side portion 32 which extendsforwardly from a transverse end wall 34 and is in close fittingrelationship with the outer wall surface of at least a portion of theplastic body member. A portion of tubular side portion 32 can be taperedat 36 in order to provide a thickened portion adjacent the enlarged shoeportion and a thinner portion at the front end thereof. Conventionalmetal caps are of uniform thickness. The thickened rear end portionprovides support for a gun extractor means (not shown) while the thinnerportion at the front end of the metal cap provides a better fit betweenthe metal cap and the plastic body member. The tapered forward end 36also helps to prevent cutting off of the plastic body which sometimeshappens with a thick, sharp-edged metal cap.

As can be seen in FIG. 2 the tapered tubular side portion 32 causes thelower end of the plastic body member 12 to be forced inwardly graduallyso as to form a portion of lesser inside diameter than the remainingforward end of the plastic body. This lesser diameter becomes importantwhen the lower skirt (not numbered) of the filler wad 18 (shown inFIG. 1) is forced down tightly so as to effect a water seal beforefiring and a gas seal upon ignition of the cartridge. It is noted thatwhen the lower end of the plastic body is forced inwardly with a metalhead having a uniform thickness, the point where the top of the metalhead meets the plastic body is more sensitive to cutoff.

provide a novel cap The transverse end wall 34 of the metal cap extendsoutwardly past the outer wall surface of the plastic body member andthen extends forwardly and inwardly to form an annular rim means 38 withthe tubular side portion 32. End wall 34 also has an annular fold 40integrally formed therein which projects forwardly and outwardly fromthe end wall 34 towards the tubular side portion 32 to end apredetermined distance 42 therefrom. It can be seen that the fold 40defines a cavity 44 with the rim 38 and the tubular side portion 32 inwhich the enlarged shoe portion 26 of the plastic body is confined. Itcan also be seen that the enlarged shoe is substantially thicker thandistance 42 so that unless the plastic shoe is substantially thickerthan distance 42 so that unless the plastic shoe is reworked andlevelled out, it cannot be pulled out of the cavity 44. The forcenecessary to pull the plastic body out of the metal cap obviouslydepends on several variables including distance 42, thickness of plasticbody, etc. However, preliminary tests indicate the force required to beabout 390 pounds as compared to a force of about 175 pounds required topull a plastic tube out of a conventional metal cap-basewad design.

The transverse end wall 34 also includes an integrally formed primerpocket 46 in which a primer cup 48 is positioned. Primer pocket 46includes a forwardly extending cylindrical side portion 50 and an anvilportion 52 integrally formed with the front end of the cylindricalportion. Anvil 52 extends rearwardly toward the transverse end wall andhas a conical side wall 54 which grades to a cylindrical impact end 56.The forward end of the conical side wall is thickened to provideadditional rigidity for primer sensitivity. Formed in anvil 52 are aplurality of flash hole openings 58.

The specifics of the primer means and the method of forming theone-piece cup and anvil will be the subject matter ofa separate patentapplication and need not be detailed at this point.

Referring back to FIG. 3, it can be seen that upon firing of thecartridge, the explosive pressure generated will tend to cause the fold40 to collapse toward air space 60. Explosive gases enter between thefold 40 and the enlarged shoe 26 caused by the metal head 14 movingoutwardly towards the gun chamber and shown in an exaggerated way inFIG. 3. The explosive gases, however, will act against the thinnedflange 30 and force the flange against the inside surface of the metalcap, thereby effecting a gas seal. In the absence of flange 30, e.g., inFIG. 3, the explosive gases can enter between the inside surface 22 ofthe plastic tube and the inside surface 62 of the metal cap to force therim flange 28 against the inside surface of the metal rim at 64.

It should be obvious that with the elimination of the basewad there ismore space or volume available within the cartridge shell. If the loadedcartridge is to be used in a conventional gun, i.e., with a chamberhaving a conventional length, the extra space either must be taken up byadditional propellant, shot load, or filler wad means. An alternative,in which the ballistics could remain the same, and which would requiremodifications to the gun, could cut down the overall length of thecartridge so as to result in a mini-shell", e.g., 2 inches long insteadof 2% or 3 inches, which are the conventional shotshell lengths. Themodified gun to handle such a shortened shell would have manyadvantages, not only in functioning but in economics.

FIG. shows a modified metal head which does not include the integralbattery cup and anvil assembly which is shown in FIGS. 1, 2, and 4.Primer pocket 46 is shown with a transverse end wall 66 having a flashhole opening 68 and a separate anvil element 70.

From FIGS. 2 and 5, it can be seen that the thickness of the transverseend wall 34 is not uniform but rather tapered toward the primer pocket46 so as to have its maximum thickness near the central primer pocket.Inasmuch as the metal head is formed from sheet metal, which is ofuniform thickness prior to being fed into the cap-making machine, itwould be expected under conventional metal forming procedures that thetransverse end wall 34 would be of constant thickness approximatelyequal to the original sheet metal thickness.

By providing maximum thickness of the transverse wall 34 adjacent theprimer opening, the transverse end wall is strengthened in the manner ofa truss in which the connecting end portion is free to hinge or pivot.The wall 34 acts as a three-dimensional plate supported or hinged on itsannular edge. The thickened portion of the end wall adjacent the primeropening resists deformation under a central impact load such as wouldoccur by a firing pin impacting against a primer. This resistance todeformation is important for primer sensitivity. In the absence of aback-up basewad means, the impact of the firing pin necessary to ignitethe priming mix must be absorbed entirely by the primer means and thesupporting metal head. For this reason, the tapered anvil and thetapered transverse end wall are more significant in this combination,i.e., without a base wad. However, it seems obvious that the body to capattaching means can be utilized without the additional improvements tothe primer anvil and the transverse end wall. It should also be obviousthat the improvements to the primer anvil and the transverse end wallwill also be important in other situations outside of the combination.

What is claimed is:

l. A shotgun shell comprising a tubular body member made of plasticmaterial and a metal cap member which closes off one end of said plasticbody member, said one end of said plastic body member having an enlargedfoot means, said metal cap member having means integrally formedtherewith to engage the inner and outer wall surfaces of said plasticbody member at a point forwardly of said enlarged foot means to compresssaid plastic body member and to lock the metal cap member thereto, saidenlarged foot means comprising an annular, flanged, rim portion whichextends transversely outwardly from the outer wall of said tubular bodymember and a second annular, flanged, gas sealing portion extendingtransversely in a direction opposite to said rim portion.

2. A shotgun shell as recited in claim 1 wherein said gas sealingflanged portion is thinner than said flanged rim portron.

3. A shotgun shell as recited in Claim 1 in which said metal cap membercomprises a cup-shaped sheet metal member, said sheet metal cap membercomprising a tubular side portion, a transverse end wall to close offthe breech end of the shell and an outwardly projecting rim portioninterconnecting said tubular side portion and said transverse end wall,said tubular side portion extending forwardly in close fittingrelationship with at least a portion of the outer wall surface of theplastic body member, said means locking the plastic body member to themetal cap member comprising an integrally formed annular loop meansextending forwardly from said transverse end wall to define a cavitywith said rim portion and said tubular side wall portion in which saidenlarged foot means is compressingly held in place.

4. A shotgun shell as recited in claim 1 in which said metal cap memberis made of sheet metal and comprises a tubular side portion which is inclose fitting relationship with a part of the outer wall surface of theplastic tubular body member, an outwardly projecting rim portion, and atransverse end wall, said transverse end wall having a primer pocketformed centrally therein, said primer pocket being defined by anintegrally formed battery cup portion, said battery cup portion having acylindrical battery side portion integrally formed with an extendingforwardly from said transverse end wall and a battery forward end wallportion connected thereto, said forward end wall portion having an anvilintegrally formed therewith extending rearwardly toward said transverseend wall, and flash hole means formed in said forward end wall portion.

5. A shotgun shell as recited in claim 1 wherein said plastic bodymember is biaxially oriented.

6. A shotgun shell as recited in claim 1 wherein said sheet metal capmember includes a primer pocket and anvil integrally formed therein.

7. A shotgun shell comprising a deformable plastic body member and asheet metal cap member, means attaching said metal cap member to saidbody member, said cap member comprising a tubular side portion and atransverse end wall, said transverse end wall having a primer pocketmeans formed integrally therein, said transverse end wall being taperedso as to provide a maximum wall thickness adjacent said primer pocketmeans thus providing desirable rigidity of the transverse end wall forrequired primer sensitivity.

8. A shotgun shell as recited in claim 7 in which said plastic bodymember has a permanently deformed annular, enlarged foot means at thebreech end of the shell, said transverse end wall having an integrallyformed, annular, fold means extending forwardly therefrom and spacedlaterally a predetermined distance from said cap tubular side portion toabut said enlarged foot means without cutting into the plastic so as toform said cap to body attaching means and also to add rigidity to saidtransverse end wall.

9. A shotgun shell as recited in claim 7 in which an anvil means isintegrally formed with said primer pocket means.

10. A shotgun shell as recited in claim 7 in which at least a portion ofsaid tubular side portion of the metal cap member is tapered forwardlyto provide a thinner section at the forward end of said tubular sideportion.

11. A shotgun shell comprising a tubular body member made of deformableplastic material and a sheet metal cap member which closes off one endof said plastic body member, said one end of said plastic body memberhaving a permanently deformed enlarged foot means integrally connectedthereto by a connecting plastic portion which is thinner than saidtubular body member, said sheet metal cap member having a tubular sideportion and a transverse end wall to close off the breech end of theshell, said transverse end wall having an integrally formed, annularloop means extending forwardly therefrom, said annular loop means havinga curved forward end which is located adjacent the tubular side portionof the sheet metal cap in close-fitting relationship to said thinconnecting plastic portion of said plastic body member, the curvedforward end of the loop means and the tubular side portion of the sheetmetal cap acting in compression to lock the enlarged foot means and theplastic body to the sheet metal cap.

12. A shotgun shell as recited in claim 11, wherein said enlarged footmeans comprises at least one annular flanged portiou integrally formedtherewith and extending in a transverse direction to said tubular bodymember.

1. A shotgun shell comprising a tubular body member made of plasticmaterial and a metal cap member which closes off one end of said plasticbody member, said one end of said plastic body member having an enlargedfoot means, said metal cap member having means integrally formedtherewith to engage the inner and outer wall surfaces of said plasticbody member at a point forwardly of said enlarged foot means to compresssaid plastic body member and to lock the metal cap member thereto, saidenlarged foot means comprising an annular, flanged, rim portion whichextends transversely outwardly from the outer wall of said tubular bodymember and a second annular, flanged, gas sealing portion extendingtransversely in a direction opposite to said rim portion.
 2. A shotgunshell as recited in claim 1 wherein said gas sealing flanged portion isthinner than said flanged rim portion.
 3. A shotgun shell as recited inClaim 1 in which said metal cap member comprises a cup-shaped sheetmetal member, said sheet metal cap member comprising a tubular sideportion, a transverse end wall to close off the breeCh end of the shelland an outwardly projecting rim portion interconnecting said tubularside portion and said transverse end wall, said tubular side portionextending forwardly in close fitting relationship with at least aportion of the outer wall surface of the plastic body member, said meanslocking the plastic body member to the metal cap member comprising anintegrally formed annular loop means extending forwardly from saidtransverse end wall to define a cavity with said rim portion and saidtubular side wall portion in which said enlarged foot means iscompressingly held in place.
 4. A shotgun shell as recited in claim 1 inwhich said metal cap member is made of sheet metal and comprises atubular side portion which is in close fitting relationship with a partof the outer wall surface of the plastic tubular body member, anoutwardly projecting rim portion, and a transverse end wall, saidtransverse end wall having a primer pocket formed centrally therein,said primer pocket being defined by an integrally formed battery cupportion, said battery cup portion having a cylindrical battery sideportion integrally formed with and extending forwardly from saidtransverse end wall and a battery forward end wall portion connectedthereto, said forward end wall portion having an anvil integrally formedtherewith extending rearwardly toward said transverse end wall, andflash hole means formed in said forward end wall portion.
 5. A shotgunshell as recited in claim 1 wherein said plastic body member isbiaxially oriented.
 6. A shotgun shell as recited in claim 1 whereinsaid sheet metal cap member includes a primer pocket and anvilintegrally formed therein.
 7. A shotgun shell comprising a deformableplastic body member and a sheet metal cap member, means attaching saidmetal cap member to said body member, said cap member comprising atubular side portion and a transverse end wall, said transverse end wallhaving a primer pocket means formed integrally therein, said transverseend wall being tapered so as to provide a maximum wall thicknessadjacent said primer pocket means thus providing desirable rigidity ofthe transverse end wall for required primer sensitivity.
 8. A shotgunshell as recited in claim 7 in which said plastic body member has apermanently deformed annular, enlarged foot means at the breech end ofthe shell, said transverse end wall having an integrally formed,annular, fold means extending forwardly therefrom and spaced laterally apredetermined distance from said cap tubular side portion to abut saidenlarged foot means without cutting into the plastic so as to form saidcap to body attaching means and also to add rigidity to said transverseend wall.
 9. A shotgun shell as recited in claim 7 in which an anvilmeans is integrally formed with said primer pocket means.
 10. A shotgunshell as recited in claim 7 in which at least a portion of said tubularside portion of the metal cap member is tapered forwardly to provide athinner section at the forward end of said tubular side portion.
 11. Ashotgun shell comprising a tubular body member made of deformableplastic material and a sheet metal cap member which closes off one endof said plastic body member, said one end of said plastic body memberhaving a permanently deformed enlarged foot means integrally connectedthereto by a connecting plastic portion which is thinner than saidtubular body member, said sheet metal cap member having a tubular sideportion and a transverse end wall to close off the breech end of theshell, said transverse end wall having an integrally formed, annularloop means extending forwardly therefrom, said annular loop means havinga curved forward end which is located adjacent the tubular side portionof the sheet metal cap in close-fitting relationship to said thinconnecting plastic portion of said plastic body member, the curvedforward end of the loop means and the tubular side portion of the sheetmetal cap acting in compression to lOck the enlarged foot means and theplastic body to the sheet metal cap.
 12. A shotgun shell as recited inclaim 11, wherein said enlarged foot means comprises at least oneannular flanged portion integrally formed therewith and extending in atransverse direction to said tubular body member.